<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
</head>
<body>
  <select>
    <option value="0">男</option>
    <option value="1">女</option>
    <option value="2">保密</option>
  </select>
</body>
</html>